A week later he stabbed sex worker Ladda Nimphet, and her boss Herbert Richard Norris to death in a Fort St massage parlour. The same night he also tried to kill sex worker Angkana Chaisamret.

At the time he told police he had a second personality called "Hell" that drove him to commit the murders. He also said his offending was the result of a drug-induced psychotic episode.

Judge Carruthers said there was a "marked aspect of planning" to the murders.

"It was brutal offending of the worst kind," he said.

"We have submissions from the families of his victims. (Poulter) tells us that when he read those he became very upset and was deeply saddened that the family members had got no help for the trauma inflicted by him. At the end of our discussions today he again said that he was deeply remorseful and sad about what happened and that he felt strongly for the families of his victims."

A psychological report presented to the board showed Poulter was still at moderate risk of violent offending and moderate to low risk of further sexual offending.

Judge Carruthers said Poulter had done "exceptionally well" in prison and "really educated himself" - but there was still a significant concern.

"Today there is no question that he can be released on parole. We believe there are many more complications to this situation which are yet to be addressed and no doubt will be teased out during the next programme."

Judge Carruthers said Poulter would participate in an adult sex offenders treatment programme, and appear before the board again in 12 months.